Stewart, Dugald, 1753-1828, Scottish philosopher. He studied at the Univ. of Edinburgh, later becoming professor of mathematics (1775-85) and of moral philosophy (1785-1810). After retiring he devoted himself to writing. A student of Thomas Reid and strongly influenced by him, Stewart is credited with aiding in the forming of the Scottish school of philosophy. His work was largely an exposition of Reid's philosophy, accepting the existence of the external world and applying the principle of common sense to the problems of philosophy. An eloquent lecturer and a brilliant writer, he is noted for these abilities rather than for any original philosophical development. Among his works are Outlines of Moral Philosophy (1793), Elements of the Philosophy of the Human Mind (3 vol., 1792-1827), and Philosophical Essays (1810).